BPH

Question 1

BPH overview

Answer 1

-Most common benign tumor in men
-Risk factors
-Age-related- 55-60 start
-force, quantity, etc. of urine decrease
-Possible genetic predisposition (maybe)
-main symptoms- cant urinate

-Pharmacological pathophysiology
-Dihydrotestosterone (DHT)- Inhibits cell death and stimulation of stroma collagen production

Question 2

overall tx approach

Answer 2

watchful waiting
-elevated PSA
-<7 is normal - watchful waiting

Question 3

alpha 1 blockers

Answer 3

-MOA – relaxes smooth muscle of bladder neck and prostate
-urinary retention!
Indications: HTN and BPH

-Pharmacokinetics
-Absorption: PO
-Distribution: highly protein bound
-Metabolism: no cyp450 DDI
-Elimination: excreted in bile, urine and feces
 
-ADRs
-CNS effects - headache (migraine)
-CVS effects - orthostatic hypotension, tachycardia
-edema
-Sexual dysfunction (ejaculatory)

-Dosing – QHS (except prazosin is tid)

-Drug list “zosin” drugs
-Prazosin (Minipres)
-Doxazosin (Cardura)
-Terazosin (Hytrin)

Tamsulosin (Flomax) for BPH only
-Less CVS effects
-More ejaculatory dysfunction (phantom ejaculation)

-Silodosin (Rapaflo) for BPH only
-Less dizziness than tamsulosin
-Most ejaculatory dysfunction of all alpha1 blockers
-Has a lot of CYP450 DDIs

-Alfuzosin (Uroxatral) – for BPH only
-Best tolerated

Question 4

5-alpha reductase inhibitors

Answer 4

-Category X – pregnant women should not even touch the drug
-MOA: testosterone derivative that blocks 5a reductase -> increase DHT synthesis in prostate gland, skin and other target tissues
-reduce prostate size! (alpha 1 doesnt)
-alpha is better at tx of urinary retention
-bc of this you can use them together
-improvement within 6 months *- set goals with pt

-indications: BPH and male pattern baldness

-Pharmacokinetics
-Absorption: PO
-Metabolism: hepatic

-ADRs
-Sexual dysfunction (decreased libido, ED, testicular pain).

-DDIs – CYP450 substrate

-Drug list: “-steride” ending
-Finasteride (Proscar, Propecia) – can be used for BPH and male pattern baldness
-shampoo option too
-Dutasteride (Avodart)
-Newer drug, blocks type I and type II 5alpha reductase - not yet FDA approved for male pattern baldness

Question 5

tadalafil

Answer 5

-cialis
-MOA: PDE 5 inhibitor. (mostly used for Erectile dysfunction)
-works on nitric oxide
-can take low dose everyday or as needed
-longer half life than sildenafil -> dont have to take it as much -> preferred
-smooth muscle relaxation in the urethra, bladder, and prostatic stroma and capsule can help relieve BPH symptoms
-increased vascular perfusion of the lower urinary tract (relieves pelvic arterial insufficiency and ischemia which then causes changes in the prostatic structure)
-may modify afferent nerve signaling from the bladder, urethra, and prostate
-headache

Question 6

herbal therapy: saw palmetto

Answer 6

-MOA: inhibits the 5alpha reductase enzyme
-CI in pregnancy and women of child bearing age (b/c of hormonal effects)
-ADRs – h/a, HTN, GI effects, back pain
-DDIs – anticoagulants, antiplatelet drugs (incr bleeding risk), OCs
-anti-inflammatory ?
-decrease prostate size

Question 7

surgical therapy

Answer 7

-if refractory to tx